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41.
42.
The widespread assumption that cytoplasts generated from human polymorphonuclear leukocytes (PMNs) are vesicles consisting solely of cytoplasm surrounded by plasma membrane and devoid of granule activity remains to be tested. PMN cytoplasts were prepared by centrifugation of intact cells on a Ficoll step gradient in the presence of cytochalasin B. Two granule membrane markers, Mol, a fluorometrically detectable antigen, and cytochrome b, both of which have been shown to translocate to the plasma membrane during granule release, were compared for their activity in cytoplasts and intact PMNs. We found that the amount of Mol detected on the plasma membrane of intact PMNs, as compared with other membrane markers (such as antigens LFA-1 and beta 2m), increased 1.6- fold upon exposure of PMNs to Ficoll plus cytochalasin B prior to centrifugation. Another twofold increase in Mol expression occurred upon cytoplast preparation. Release of the granule enzymes, vitamin B12- binding protein, and lysozyme were also followed and correlated well (r = .78 and .92) with the amount of Mol antigen present on the cell surface. Cytochrome b was also found to be higher (1.4-fold) on plasma membranes isolated from cytoplasts than on plasma membranes isolated from intact control cells. These results indicate that some fusion of granule membranes and plasma membranes occurred during treatment of PMNs with Ficoll plus cytochalasin b and during cytoplast preparation. 相似文献
43.
44.
Styles LA; Schalkwijk CG; Aarsman AJ; Vichinsky EP; Lubin BH; Kuypers FA 《Blood》1996,87(6):2573-2578
Acute chest syndrome (ACS) is associated with significant morbidity and is the leading cause of death in patients with sickle cell disease (SCD). Recent reports suggest that bone marrow fat embolism can be detected in many cases of severe ACS. Secretory phospholipase A2 (sPLA2) is an important inflammatory mediator and liberates free fatty acids, which are felt to be responsible for the acute lung injury of the fat embolism syndrome. We measured SPLA2 levels in 35 SCD patients during 20 admissions for ACS, 10 admissions for vaso-occlusive crisis, and during 12 clinic visits when patients were at the steady state. Eleven non-SCD patients with pneumonia were also evaluated. To determine if there was a relationship between sPLA2 and the severity of ACS we correlated SPLA2 levels with the clinical course of the patient. In comparison with normal controls (mean = 3.1 +/- 1.1 ng/mL), the non- SCD patients with pneumonia (mean = 68.6 +/- 82.9 ng/mL) and all three SCD patient groups had an elevation of SPLA2 (steady state mean = 10.0 +/- 8.4 ng/mL; vaso-occlusive crisis mean = 23.7 +/- 40.5 ng/mL; ACS mean = 336 +/- 209 ng/mL). In patients with ACS sPLA2 levels were 100- fold greater than normal control values, 35 times greater than values in SCD patients at baseline, and five times greater than non-SCD patients with pneumonia. The degree of SPLA2 elevation in ACS correlated with three different measures of clinical severity and, in patients followed sequentially, the rise in SPLA2 coincided with the onset of ACS. The dramatic elevation of SPLA2 in patients with ACS but not in patients with vaso-occlusive crisis or non-SCD patients with pneumonia and the correlation between levels of SPLA2 and clinical severity suggest a role for SPLA2 in the diagnosis and, perhaps, in the pathophysiology of patients with ACS. 相似文献
45.
Andrea LA?TOVKOVá Pavlina KLUSá?KOVá Zdenka FENCLOVá Vincent BONNETERRE Daniela PELCLOVá 《Industrial health》2015,53(6):562-568
The objective of this study is to describe a case-series of potassium aluminium
tetrafluoride (KAlF4)-induced occupational asthma (OA) and/or occupational
rhinitis (OR). The study involves five patients from a heat-exchanger production line who
were examined (including specific inhalation challenge tests) for suspected OA and/or OR
caused by a flux containing almost 100% KAlF4 − with fluorides’ workplace air
concentrations ranging between 1.7 and 2.8 mg/m3. No subject had a previous
history of asthma. All five patients had a positive specific challenge test (three
patients were diagnosed with OA alone, one with OR and one with both OR and OA). At the
follow-up visit, after three years on average, all patients needed permanent
corticosteroid therapy (four topical, one oral). After elimination from the exposure, only
one of the observed subjects gave an indication of an improvement, two subjects stabilized
and two worsened. Our case series focuses on the correlation between patients’ exposure to
fluorides in air-conditioner production and the subsequent occurrence of OR/OA. Currently,
it is uncertain whether these OR/OA were caused by hypersensitivity or irritation. 相似文献
46.
目的探讨腹腔镜手术对不孕症患者的诊断及治疗价值。方法回顾性分析新疆医科大学第一附属医院2010年9月-2014年5月收治的319例不孕症患者的临床资料,对所有患者行腹腔镜下诊断及相应的手术治疗(包括盆腔粘连分解、输卵管造口术、输卵管灼断术等)。结果 319例患者腹腔镜术中检查与术前子宫输卵管碘油造影结果的符合率为72.1%(230/319),其中有43例术中发现子宫肌瘤,56例术中发现输卵管系膜囊肿,8例患者术中发现子宫内膜异位症,有2例患者诊断为盆腔结核,1例术中发现结肠肌瘤(术前考虑卵巢囊肿),其余为不同程度的盆腔慢性炎症。轻度粘连69例,妊娠21例,宫外孕2例,妊娠率33.33%。中重度粘连250例,其中行灼断术34例,灼断术患者后行体外受精及胚胎移植(IVF-ET),妊娠13例,妊娠率38.23%(13/34)。其余216例,失访3例,妊娠31例,宫外孕3例、妊娠率15.9%。结论腹腔镜对诊断输卵管性不孕及盆腔疾病有重要价值,子宫输卵管造影仅能初级筛查,诊断价值有限。在治疗输卵管粘连梗阻中,腹腔镜的治疗价值有待进一步探讨,临床预后与盆腔炎症的程度有关,应个体化选择手术方案。 相似文献
47.
A New Variant of Hereditary Hemolytic Anemia With Stomatocytosis and Erythrocyte Cation Abnormality 总被引:4,自引:1,他引:4
MILLER DENIS R.; RICKLES FREDERICK R.; LICHTMAN MARSHALL A.; LA CELLE PAUL L.; BATES JONATHAN; WEED ROBERT I. 《Blood》1971,38(2):184-204
A new variant of congenital hemolyticanemia associated with stomatocytosis,reticulocytosis, decreased osmotic fragility, type I autohemolysis and shortened erythrocyte survival without specific splenic sequestration was discoveredin three siblings of Swiss-German ancestry. Increased intracellular sodium(two to three times normal) and slightlydecreased intracellular potassium weredetected. Total sodium efflux was eight-fold greater than normal but total potassium influx was normal and ouabain-sensitive potassium influx was decreased.The ouabain-sensitive sodium efflux:potassium influx ratio was 26:1 ratherthan the 3:2 ratio noted in normal cells.The consanguineous parents, four othersiblings, and 44 other family membershad mild stomatocytosis, reticulocytosis,and, when studied, decreased osmoticfragility, increased autohemolysis, intermediate abnormalities of cation content,cation flux, and moderate shortening oferythrocyte survival. Autosomal dominant inheritance was suggested. Noabnormalities of RBC enzymes, hemoglobin or lipids were observed. No abnormalities of membrane protein weredetected on acrylamide gel. Substratedepletion of these hypermetabolic cellsresulted in intracellular dehydrationwith potassium loss in excess of sodiumgain and decreased deformability. Although the exact nature of the defectresponsible for hemolysis is unknown,this syndrome differs from other hereditary hemolytic anemias associated withstomatocytosis. Submitted on December 21, 1970 Revised on March 16, 1971 Accepted on March 29, 1971 相似文献
48.
Human platelet membrane glycoproteins IIb and IIIa (GPIIb and IIIa) were incorporated into phospholipid vesicles by the reverse-phase technique to assess the ability of GPIIb and IIIa to function as a Ca2+ channel. Movement of Ca2+ across the lipid bilayer was quantitated by injection of proteoliposomes with encapsulated Fura-2 into Ca2+ buffers and measurement of Fura-2 fluorescence as an indicator of Ca2+ influx. Reciprocally, to assess the function of proteins in an inside-out orientation, Ca2+-loaded vesicles were injected into Ca2+-free buffer and Ca2+ efflux monitored by a calcium electrode. Incorporation of the IIb-IIIa complex produced significant facilitation of Ca2+ movement across the lipid bilayer. No net transmembrane Ca2+ movement was seen with dissociated IIb and IIIa. Movement of Ca2+ was proportional to the transmembrane Ca2+ gradient. Ca2+ movement into the vesicles was inversely proportional to extravesicular NaCl from 25 to 150 mmol/L, analogous to several studies in the intact platelet. Adenosine triphosphate had no effect on Ca2+ movement into or out of the vesicles. Specific inhibition of a Ca2+ shift into the vesicles was seen with M148, a monoclonal antibody to IIb/IIIa, while no inhibition was observed with a panel of other anti-IIb/IIIa monoclonal antibodies. This suggests that a specific site on the complex or orientation of the complex is essential for calcium channel function. These data demonstrate that the GPIIb/IIIa complex can serve as a passive Ca2+ channel across a phospholipid bilayer and has the potential to play a role in Ca2+ flux across the platelet plasma membrane. 相似文献
49.
目的 对比分析单纯后路内固定+一期经腰椎间孔病椎间病灶清除(TLIF)与经典的前后联合手术在布氏杆菌性脊柱炎患者中的临床疗效及安全性。 方法 对我院2015年1月至2017年12月收治的93例布病性脊柱炎患者的临床资料进行分析。按手术方式分为观察组(45例)和对照组(48例)。对两组患者的基础数据、临床指标、术前术后各项指标水平以及术后并发症、植骨治愈情况。 结果 观察组与对照组基础数据比较,差异无统计学意义(P>0.05)。观察组患者的手术时间、住院天数、术中出血量及术后下床时间均明显低于对照组(P<0.01)。两组患者术后3个月的ODI、VAS、CRP、ESR及Cobb角均明显低于术前(P<0.05);术后3个月,观察组患者的ODI、VAS、CRP、ESR及Cobb角均明显低于对照组(P<0.05)。观察组术后并发症发生率(4.4%)明显低于对照组(25.0%)(Χ2=7.674,P<0.01)。 结论 TLIF治疗布氏杆菌性脊柱炎患者的临床疗效突出,安全性较好,更有利于患者术后身体的恢复。 相似文献
50.
MA Suckow SL Voytik-Harbin LA Terril SF Badylak 《Journal of investigative surgery》2013,26(5):277-287
Small instestinal submucosa (SIS) is an easily produced material that has been used experimentally for tissue engineering. To evaluate the ability of SIS to facilitate bone growth within a long-bone defect, a segment of the radius was surgically removed in adult, female Sprague-Dawley rats. The defect was either left unfilled or implanted with SIS, demineralized cortical bone (DMCB), or ovalbumin. The defect was evaluated radiographically and histologically after 3, 6, 12, and 24 weeks. Tissue remodeling within the defect was evident by week 3 in SIS- and DMCB-treated rats. Filling was characterized initially by infiltration of mononuclear cells and extracellular material in SIS-implanted rats and multifocal remodeling bone particles and cartilage formation in DMCB implanted rats. Cartilage was observed as early as 3 weeks and bone as early as 6 weeks in SIS-implanted rats. Filling of the defect arose from multiple foci in DMCB-implanted rats, but was contiguous with and parallel to the ulnar shaft in SIS-implanted rats, suggesting that defect repair by SIS may be conductive rather than inductive. Rats in which the defect was left unfilled demonstrated slow but progressive filling of the defect, characterized by mononuclear cell infiltrates and fibrous extracellular material. In summary, SIS facilitated rapid filling of a longbone defect. These results suggest that SIS may be useful as a bone repair material. 相似文献